Can You Be Cured?
by Massacre13
Summary: Sarah Jay, daughter of Hades, has been hit hard by the Gaea War, and along with Percy, Annabeth, Nico and Leo, is sent to the Avengers for But with an old foe forming a new army, will the damaged demi-gods be ready? Or will they remain, incurable? *Set after Mark of Athena, contains mild swearing and Stark humour (hopefully)*
1. Chapter 1

Sarah Jay had never had much time for joking around, after all, she was at work 24/7, either running errands for her father or keeping the waiting room in check. It was her brother who got all the exciting missions. At least, he did, until the war with Kronos. She had had training, so much training it was almost impossible to train further, but war was something completely different. She'd fought monsters, spirits, demi-gods and even mortals, but she'd never been in a war.

The pain was excruciating – both physical and mental. Of course, a child of Hades should never show their fear, but night after night, nightmare after nightmare, it was slowly becoming too much. And then there was the second war, and the whole cycle all over again, but so much worse.

After Nico was saved from the clutches of Ephialtes and Otis, and the famous heroes Percy Jackson and Annabeth Chase… escaped from Tartarus, Gaea and the giants was defeated, but at a terrible cost. Her sister, Hazel Levesque, and the boyfriend, Frank Zhang, were dead, along with hundreds of other demi-gods, Greek and Roman. Of course, they were placed in Elysium, but the grief was still overwhelming, and she hadn't even known them that well. She wished she had.

The nightmares progressed with frightening power and frequency. It was rare she was called to the surface, to Camp Half-blood, and it was even rarer she was allowed to go, but today she had been.

Sitting at a table along with four other demi-gods in what was known as 'The Big House', she kept her back straight, her long dark hair plaited behind her, hands on her lap as the camp leader, Chiron addressed them.

"Demi-gods, you have been called here today, because the Gods have a proposition for you." They sat listening attentively – Sarah knew the other demi-gods at the table. One was her brother, Nico DiAngelo, another was Percy Jackson, favoured hero of Olympus, the third was his girlfriend, daughter of Athena and infamous solver of the Mark of Athena, Annabeth Chase, and the last, whom she was least acquaintance with, was a son of Hephaestus, Leo something-or-other.

Chiron continued.

"There is a team of mortals known as the Avengers, who are accompanied by a Norse God, Thor." There was a light roll of thunder outside "They were responsible for the downfall of the Alien Race, last year, just before Gaea's forces rose." A shiver slithered down Sarah's spine. "The Oracle has predicted that a new force will rise, and the God's believe that we will need you all in your best health. For once I do not disagree with them." His face was serious, aged by war and death.

"We are in good health," Percy said, breaking the short awkward silence. "No one's injured, we're all still training."

"_Mental_ health, Perseus." Chiron said, and Percy went quiet "The Gods propose that you join the Avengers – take some time off, in other words." The room was silent "It will do you good." He finished.

"All of us? With the Avengers?" Leo said slowly.

"Yes."

"Even her? Who are you anyway? I've never seen you before." He turned to Sarah, but her focus stayed ahead of her.

"That's my sister, Sarah." Nico said gruffly, folding his arms "Why is she coming anyway?"

"Maybe Sarah has her own problems, Mr DiAngelo." Chiron said sternly, with a glance in her direction. She did not respond in any way, and simply remained silent. Percy and Annabeth avoided looking at her, as she did them. The very sight of them was more than enough to stir up…_bad_ memories. She had no desire to be around them everyday for the foreseeable future. If a new war broke out, she could be called when she was needed.

She would _not_ go with the others to the Avengers, she would _not_ let the nightmares get out of hand, and she would _not_ spend everyday surrounded by her memories. She was Sarah Jay, daughter of Samantha Jay and Lord Hades, and she would _not_ be joining anyone in this ridiculous quest.

* * *

Sarah stood in the lobby of Stark Tower with a death-glare worthy of making the most fearless man in the world cower before her. So naturally, when Tony Stark walked out of the elevator he nearly dropped dead on sight. He stopped for a moment to recuperate, and then continued.

"Jarvis said you were down here." He declared lavishly. The demi-gods said nothing, although Leo had gone a bright and dangerous shade of red as his knees trembled.

"Standing in the doorway is rude." Tony said, pointing slightly, and Leo seemed to jump into action, shoving Percy and Annabeth forwards and pushing them the whole way into the elevator. He made a slight squeaking sound through his lips, and Tony raised an eyebrow as Nico stepped in the elevator. The lobby was empty. Tony looked around obviously.

"Where's the other one?" Annabeth pointed behind him, and he turned, nearly fainting again as Sarah's death-glare bore down on him. Leo shoved her, earning his own death-glare, but he didn't care.

"Don't glare at Tony Stark!" Leo squealed as the elevator doors closed, and then launched into a speech. "Oh my Gods, Mr Stark, I don't mean to fan-girl but oh my Gods you're here! We're meeting the _actual_ Tony Stark! I am such a huge fan, I mean, you are amazing, I love your work, and the Iron Man suit, the design is amazing! I love how you've done the tower and the…" Tony stared smugly, forgetting the glare from the demi-god behind him, absorbing and practically basking in the surge of compliments. Sarah hated him already.

The other demi-gods had their bags packed in what looked like duffel bags that were slung over their shoulders (naturally Leo's was overly technical, Annabeth's was undoubtedly stuffed with books and maps, Percy's was full of swimming trunks and blue food colouring, and Nico's contained armoury). Sarah had nothing with her save for her weapons that she kept carefully concealed around her body. She wasn't planning on staying long, and even if she did, a quick shadow-travel to the Underworld would be all it would take to change clothes. She saw no reason to pack, and as she was here against her will, why should she?

Leo didn't stop talking until the elevator doors opened again, and then his mouth seemed to have suddenly developed a zip across it.

Tony led the way out and into a large living room that also had a bar and kitchenette inside, as well as several sofas and the largest flat-screen television Sarah had ever seen, not that she'd seen many. It had a spectacular view that spread across Manhattan and across the sea, or, it would have, if it hadn't been blocked by a small array of people.

"Newbies, meet the crew. Crew, newbies." Tony announced. The 'crew' was looking at them in silence, until after a moment, a man with short blonde hair stepped up and held out his hand for Percy to shake.

"Steve Rogers. It's a pleasure to meet you." Percy shook his hand.

"Percy Jackson. Ditto." Steve tilted his head slightly in confusion, but said nothing. Percy decided to take over the introductions.

"This is my girlfriend Annabeth, my friend Leo, and my cousins Nico and Sarah." Steve stood aside and pointed to each of the 'crew' in turn, who had all approached, but stayed just behind him.

"This is Dr Bruce Banner, Agent Natasha Romanoff, Agent Clint Barton, Thor, and you've already met Tony" he lowered his voice "I'm so sorry, I tried to stop him going to the lobby but he never listens to me."

"Too right, Capsicle. My tower, my rules." Leo let out another small squeak.

"Director Fury will be arriving for an introductory meeting tomorrow at 10." The red-haired woman known as Natasha, said.

"Young heroes!" Thor boomed, striding forward and grabbing Percy's hand in what had to be the strongest handshake even to exist on Earth "The tales of you on Asgard are legendary! I am honoured to be in your presence!"

"Uh…thanks?" Percy stuttered, blushing uncomfortably as his hand was released.

"We'd better let Tony show you to your rooms." Steve said, saving the teens from another attack from the asgardian god. Leo's face brightened.

"Great!" They stared at him. "Uh, I mean, yeah that's cool."

"Don't mind him, he's just… excited." Annabeth said. Percy coughed *fan-girl*. Leo glared at him. Tony grinned.

"Finally, sombody with taste. Let's go then. The sooner you're in your rooms, the sooner I can give you a tour of the tower."

"Seriously!" Leo couldn't help but squeal. Percy glanced to Annabeth. Nico sighed. Sarah glared. Tony grinned.

"Let's go then!"


	2. Chapter 2

Sarah didn't sleep much that night. She stayed awake, laid on the bed rather than in it, staring into the darkness. She felt drained. Tired. But she knew what would happen if she closed her eyes. There'd be more darkness than now, a darkness so deep even her own shadows gleamed like the sun. There'd be a laugh, the cruellest laugh she'd ever hear that would continue to ring in her ears as she ran, stumbling, falling, landing on sharp thin needles that pierced her flesh in a thousand places. There would be blood, so much blood, and then the darkness would close around her again, pulling at her, wrenching her apart, monsters closing in from all angles, and her own screaming would begin.

She shot up in bed as she opened her eyes. When had she fallen asleep? When she'd been thinking? Or was it before that? She was panting, sweat dripping down her face. She'd learned long ago not to scream.

She got up, scowled, and walked to the shower. The feel of hot water on her skin made her more alert, and when she got out, she was dressed for the day, clad in black, hair plaited, jeans slightly sticking to her skin which was not entirely dry.

She opened the door slowly. It was still dark out, probably no more than midnight. But she wouldn't be able to sleep again anyway. She'd run a few errands, do a few jobs. There was one she'd received the day before when she'd returned to the Underworld before leaving for the Tower. A man named Art Young (she'd wanted to put the word 'thou' in front of it to amuse herself, but that was unprofessional). He'd been alive for far too long, and though he was of minor significance in the grander scheme of things, to leave one unchecked was to open up a whole new set of opportunities. Opportunities they could not afford to allow.

She picked up her daggers and slipped one into her sleeve, the other into her boot as she walked. She couldn't remember the layout of the tower from the small, but extravagant tour Tony had given (if Leo hadn't fainted from excitement the minute they set foot on the workshop floor dedicated to machines and the Iron Man suits, the tour probably would have been longer).

Sarah made her way to the top floor, and found a door in the darkness that led out onto a balcony that was far too big and grandeur to be called a balcony. But still, she was outside. It was late. He'd still be out, doing what he did best – dealing drugs and stalking the houses and apartments of his ex-girlfriends. She'd looked at his file, seen what he did. She wasn't happy about it.

The wind whistled slightly from such a height, and gently tossed strands of her hair to the back of her head. She melted into the shadows and travelled to the bottom of the tower across the outer wall. She slid through streets and shot down subways until she was in the very heart of Manhattan. A two minute trip in total.

She stepped out, brushed herself down quickly, and looked around. She could sense him, his life essence. She thought she could smell him too – a horrible stench of vomit and alcohol. She walked in his direction, slipping through the alleys and small paths until he was in view, staggering away from a particular house after hurling a beer bottle at it that had smashed on the door.

She stepped out of the darkness, walked across the street to him, calm as could be. He noticed her at the last minute, turned his ugly head, the bust bottom lip drooling blood, probably from a bar fight. He sneered at her.

Her fist went to his face, cracked his nose with a splatter of blood and cartilage. He staggered backwards as her foot struck his stomach, and he stumbled, fell to his knees.

"_Bitch_," he spluttered through broken teeth. Her dagger flicked to her wrist and she put it under his throat. She slit quickly, and cleanly, and he collapsed to the pavement.

His soul rose to meet her, and stood, swaying slightly. He growled.

"_What the hell did you do_?" He wheezed.

"Art Young, you should have died last week, on Thursday the 31st at 2127 hours from a heroin overdose. Your soul has already been condemned to eternal punishment for the crimes you have committed – the most recent of which being breaking into an elderly lady's home performing burglary, arson and assault. Not the mention the stalking and attacking of your various ex-partners,"

"_Now wait a minute-_"

", or the recent attack you carried out on a school child aged 11 while she was walking home. Or mixing poisons in with various drugs you've dealt, which, coincidentally, resulted in the death of another young man. That's murder, Mr Young. You may have escaped the law, but there is no escape in death."

"_Just try it_." He snarled, and he lunged. He passed through her harmlessly, falling to the ground on the other side as she turned around.

"You're _dead_, Young. You can't hurt anyone anymore." She clicked her fingers, and the earth shuddered and shifted under her feet, splitting open to reveal the underworld below. Art stared in horror as the screams drifted up from the Fields of Punishment. Sarah leant forwards and grabbed him by the collar, hurling him in, and he screamed as he fell. The crack in the ground closed, and Sarah walked away.

* * *

She had finished and filed the report on Art by the time someone came to fetch her from her room. As it happened, her brother and the other demi-gods knew better than to disturb her. The Avengers did not.

First came the knock on the door. Sarah looked up, and then padded softly to the side of the door. She leant over and quickly turned to handle before leaning back. There was a pause, and then someone entered the room. They were pinned against the wall with a dagger to their throat in less than 2 seconds flat.

"State your name and purpose." Sarah growled.

"Steve Rogers asking that you join us for a meeting with Director Fury." He gasped, arms held behind his back, the sheer suddenness of the attack knocking the wind out of him. She let him go, and stepped aside.

"In future, don't disturb me when I'm working." She muttered, and stalked out of the room, tucking the dagger in her sleeve. She shadow-travelled to the room they had first been shown to – apparently a living room – where everyone had congregated. Steve appeared a few moments, and looked warily at her for a second before turning to the team.

"Director Fury will be here any minute. Apparently there are some things he wants us to check out."

"Does he want to check out _things,_ or do you mean he wants to check out _us_?" Nico asked from across the room, stood in the shadows, as Sarah was.

"He said gather information -"

"So it could be either." Tony finished the sentence with a sigh. "We're meeting him in conference room 3B 10 floors down, in, oh, 2 minutes ago now."

"I though he wasn't coming for another few minutes?"

"You don't have a watch on."

"He won't be happy." Agent Romanoff's voice broke the men's arguing.

"We'll meet you down there." Nico said, gesturing his head to Sarah. She nodded.

"Elevators are too cramped anyway." Percy shrugged. Tony frowned in an offended way. Leo noticed, and punched Percy on the shoulder. Sarah and Nico rolled their eyes. Sarah glared too for good measure.

"We'll meet you down there." Nico repeated with a sigh, and melted into the shadows. Sarah nodded, and did the same, following Nico's trail to the corridor outside of conference room 3B. She took up a position leaning on the wall by the door, tapping her fingers on her elbow. 3 minutes later, the elevator button dinged, and the three remaining demi-gods came stumbling out.

"In the name of Hades!" Percy exclaimed.

"Talk about a button fight." Annabeth muttered.

"I think my ribs might be broken." Leo wheezed, clutching his side. This considerably brightened up Sarah's day, and she smirked as the avengers walked calmly out of the elevator, the only sign anything had been wrong was the scowl on Tony's face and the look of victory on Natasha's.

Tony entered the room first, with the avengers and then demi-gods following. Sarah was the last to enter. Two agents, dressed in black and dark-blue flanked a man with dark skin clad in black leather with a long coat. They were stood impatiently.

"Our apologies Director." Steve said as he sat down. Sarah noticed that Natasha stayed by one side of the door, so she stayed by the other and folded her arms. Nico glanced at her, but did nothing else. The man in black looked round the room with a disgruntled face. He had an eye-patch over one eye, which reminded Sarah very vaguely of a pirate. He said nothing. There was a brief silence, before, as expected, Tony chose to speak.

"So, what brings you to my amazingly amazing abode?" He asked. The man looked at him with his eye, not turning his head.

"We've had a tip-off that a new threat may be rising."

"When aren't they?" Someone muttered. The man in black said nothing to this, but continued.

"I need you to gather information from a man who may have heard something about it."

"What exactly are we asking him about?" Bruce asked.

"What he's seen and heard recently that he would determine strange. According to the tip-off he doesn't know the implications of what he's seen, so you may need to reduce your numbers or split up to avoid him panicking."

"Ok. Who are we talking too and where do we find him."

"He's called Art Young. He lives on Surpluss Avenue, number 3, apartment 2D." The temperature dropped 10 word of thought passed through Sarah's mind: _Shit_.

"I'm afraid that won't be possible." Every head turned to her as she spoke. She surveyed them coldly.

"And why not?" The man in black asked.

"He's dead." Her answer was received with silence.

"How would you know that?" Natasha asked. Sarah didn't look at her.

"None of your business."

"You're part of a team now. _Everything_ is our business."

"Not this."

"Might be an old boyfriend?" Tony suggested. Sarah snarled.

"_Never_."

"An order?" Nico asked darkly.

"Might've been." She replied steadily, and he nodded once before continuing talking to her, this time in Greek. The words slipped from his mouth smoothly as a line of gibberish to the confusion of everyone else in the room – save for the other demi-gods of course. Fury glanced to Steve, who glanced to Bruce. Bruce shrugged. Thor watched the conversation between the siblings with a nervous look on his face. Eventually, Sarah seemed to gring her teeth together, but nodded sharply. Nico turned to Fury.

"How urgently is the information needed?"

"As soon as possible."

"Right. We'll have him in an hour." There was a pause.

"Um… I think I'm missing something here. He's _dead_, but we'll see him in an hour?"

"That's right." Nico nodded with a grim expression "Sarah will sort it out, won't you, Sarah." She growled at him. "See? All sorted."

"Just get the information." Fury said. They nodded.

"Yes sir."


	3. Chapter 3

The day was cloudy, slightly dark. It fit the mood, really. There were on the bottom floor, in Tony's garage, and after Leo had spent 10 minutes fan-girling over each ridiculously expensive car, they could get to work.

"He won't be able to stay up for long," Sarah said darkly, turning to the group "so I suggest whatever you have to say, you say it quick." She glanced to her brother, who nodded at her. She walked out into the space between the cars that led up to the exit and focused. The air grew cold, the shadows seeping towards her like liquid and she tapped her foot against the concrete. The ground split with an almighty '_crack_', setting off each wailing alarm from each car.

"Jarvis!Alarms off!" She heard Tony instruct, and the sirens stopped giving way to the eerie sound of low screaming, moaning, wisps of black shadow curling around the edges of the crack. It gave way to a large hole as it caved in, revealing a dull green light.

"Back in a sec." She muttered, and jumped. She knew they would not be able to get near the passage to the Underworld – Nico was taking care of it. The air slowed around her at her landing, so her feet gently touched the ground, toes first. She began to walk, past Eslyium where her sister, Hazel, and the boyfriend, Frank, were at peace, and then past the Fields of Asdosphel where her own mother lay (Cerberus was happy to see her as always, but she did not stop for more than a few seconds). The tall black graveyard gates rose higher than a hundred feet leading to the Fields of Punishment that wasn't really a field anymore. Since the world wars, there had been changes. Hades had overseen them himself, and she'd heard all about it from the Furies. It used to be sections, layer upon layer of the damned in eternal pain, suffering from their own specific punishment. But this was too open, too spacious. It was difficult to navigate, and terribly noisy. And of course, when the wars erupted, many unjust people were sent there, meaning it had to be bigger. And bigger it was. Like the mortals, they had built_ up_. Of course, when you're underground there's only so far 'up' you can go, but they managed it. Now the punishments were held in boxes that resembled to rooms from a mental asylum or the cells at a police station. Steel metal doors each leading to a room much larger on the inside that it appeared, and each person had their own individual punishment.

One of the best things that Sarah found, was that each 'cell' was numbered, each soul recorded. You could find anyone without the major inconvenience of having to look for them. Since her… return, she wasn't as fond of the fields of punishment as she had once been. But then, she wasn't the same person anymore either.

Art's cell was number 3 million 6 hundred thousand and 892 (3,600,892), and she found it quite easily, though it took a while to get to. She opened the door and stepped into his hell.

It appeared to be just him on a table not dissimilar to that of the lethal injection table, with wires and a needle threading into his left arm. But his face was contorted in pain as he cried and screamed and bellowed. They always said a 'bad experience' whilst high was terrifying. It was definitely working for him. She wasn't quite sure if he didn't know what was real or not anymore, and she was tempted just to leave him there – the likelihood of him having any information other than an unintelligible series of splutters was not high – but she had a job to do. And so she would do it. She always did. She walked over to the machine that appeared to be 'applying' the drug, and switched it off. He jerked awake immediately, his back arching, face twisting, panting as if he had just woken up from a nightmare. She unstrapped him from the bonds that held his wrists and ankles to the table, and forced him to stand. She felt no pity for him as he threw up over the side of the table – he was here because of his choices, choices he knew were wrong and yet pursued anyway only to cause harm and misery to others. He deserved it.

She grabbed his bicep and dragged him from the room, the door slamming shut behind them, as if it were angry for having its victim taken away. He staggered, tripping but not falling as she held him up roughly. The Furies watched her in a mixture of curiosity and anger as she removed him from their domain. After that it was pretty easy to get back up to the surface. A staircase-like structure formed at her will, and was kept as short as possible. The light beckoned them, and Sarah pushed back the feeling of sickness in her stomach, a flashback threatening to surge into her mind.

She stepped up to the surface, dragging him behind her, and threw him down onto the concrete, the disturbed and almost sickened eyes of her new 'comrades' lingering on her.

"Make it quick." She muttered as Art spluttered and gargled and put his hands to his throat.

"Jesus, that's what you do to guys down there?" Tony asked in short mocking horror.

"He's from the Fields of Punishment. His choices have put him there. We just make sure he pays for them." Sarah growled "Now ask your stupid questions before I put him back."

"Right," Natasha said, snapping out of the trance the short demonstration seemed to have had on her.

"Art Young?" He swayed on his knees, drooling slightly, his dead eyes glazed and bloodshot. "Art? Can you hear me?" Art gurgled, then spat up blood.

"What was his punishment?" Nico asked his sister. She folded her arms over her chest.

"PMT." She answered. Nico nodded.

"What's a 'PMT'?" Clint asked.

"Permanent Mental Torture."Nico answered him "It's not likely he'll be able to distinguish what's real and what isn't anymore."

"That's why he needs to get back." Sarah muttered. "Before he starts getting something back from this."

"Art," Natasha tried again, and reached out to tilt his head up so he could see her.

"Don't touch him," Sarah said quickly, pulling Natasha's hand away "If you touch him you might experience some of his memories."

"Well, that's good, isn't it? We'll be able to find out what he saw." Steve said, looking at his comrades.

"No, it's most definitely not good. The likelihood of you seeing anything that isn't his punishment is practically non-existent. You want to end up like that?"

"How is it that you can touch him then?" Sarah wanted to punch them.

"None of your business." She muttered "Just ask your stupid questions."

* * *

_Fury had called them in. Apparently, it was urgent. Urgent enough for him to come to the tower himself for the meeting, instead of sending them to him. Thor was the only one absent, away on Asgard. They sat around the table, a unanimous curiosity keeping them silent. Fury's face was grim as he addressed them._

_ "It seems," he said slowly "that our knowledge of our world, is not nearly as complete as we'd once thought." Tony bit back a sharp line of wit and waited for Fury to continue. "It has come to our attention, that there is an entire secret society living among us."_

_"What kind of society?" Clint asked from the back._

_ "Last week, we were sent footage by an anonymous source of a teenage boy, flying a winged horse."_

_"A winged horse?" Steve asked in disbelief._

_ "So, could have been CGI." Tony shrugged – technology was his forte after all. _

_ "If it had been, we would have known about it." Fury said in a condescending yet dangerous tone of voice "This is real. Since then we've been alerted to several types of cases deemed 'strange activity', and each of them concerns at least one teenager."_

_ "So, it's a secret society of crazy flying teenagers?" Tony smirked._

_ "This is not the time, Stark. We've managed to identify most of them, 5 ones of major interest, and researched their files. Most of them are trouble-makers, and one of them, according to our files, doesn't exist."_

_ "I thought SHIELD had filed on everyone?" Natasha said._

_ "So did we." Fury responded grimly, before tapping the table once. 5 screens appeared in the air over the table, like holograms, featuring a file, one for each person of interest. The first was a teenager with black hair and startling green eyes. The name read '_Percy Jackson_'. The second, a girl about the same age with blonde hair and stormy grey eyes. '_Annabeth Chase_'.The third, a boy with tanned skin, dark brown hair and brown eyes. '_Leo Valdez_'. The fourth, an extraordinarily old photograph of a young boy with dark hair and dark eyes looking embarrassedly away from the camera. '_NicoDiAngelo_'. And finally, the last screen, which had the grainy image, as if taken from an ancient CCTV camera, the barely identifiable image of a girl with pale face and dark hair. The name read _'Unknown'_. _

_ "How is that unidentifiable? She could be anyone." Bruce asked._

_ "We checked the area several times over. At the time the video was taken, no one was reported in the area. No one at all. We checked all the CCTV and video feeds in the area. There were no eyewitnesses because no one was there."_

_ "Can we see the video?" Bruce asked. Fury nodded, and touched the picture. The screen's image changed from a file to an extraordinarily grainy video. A black mass lashed itself onto the screen like a whip, merged into the form of the girl and then lashed off again, as if she had no physical form. It was less than 5 seconds long. _

_ "That's it?" Tony frowned. Fury nodded sharply. _

_"So, this secret society. What is it made of?" Steve asked. Fury looked around them, his one good eye flicking from face to face. If Thor had been there, that would have been who his eye rested on._

_ "Demi-Gods."_


End file.
